Thread: Limp tail ?

I just noticed tonight, after I caught some of his tail hair underfoot, that Dicky's tail is always down and sort of limp. It's not "dead" and there is muscle strength in the base of the tail but he doesn't seem to raise it and wave it like the other two. Trying to find video of him/them playing which gives me an idea of how he has been since honestly I can't recall if and when he changed.

Advice ? Things to look for ?